Evidence for Mississippi Valley-type lead-zinc mineralization in the Cevennes region, Southern France, during Pyrenees orogeny

摘要

The Mississippi Valley-type lead-zinc ore deposits of Cevennes region of southern France have frequently been attributed to syngenetic ore emplacement and epigenetic mineralization during Mesozoic continental extension. We report the results of new paleomagnetic analysis of MVT lead-zinc deposits in the Cevennes region that has yielded a remagnetization of Lower-Middle Eocene age that was caused by fluid interaction with the rocks. This age is consistent with radiometric ages obtained from U-Th-Pb, and Sm-Nd iso-topic systematics from samples of ore-stage fluorite from several MVT localities in the Cevennes region. These new ages for MVT deposition is interpreted to indicate that mineralization in the Cevennes region was the result of large-scale fluid-flow in the south of France during the Pyrenees orogeny.